Department of Biochemistry, Microbiology and Biotechnology, Rhodes University, Grahamstown, South Africa.
Nanomedicine. 2013 Feb;9(2):185-93. doi: 10.1016/j.nano.2012.05.020. Epub 2012 Jul 5.
The effect of silver (Ag) and gold (Au) nanoparticles on the ferroxidase activity of apoferritin showed a 110-fold increase in specific activity and a 9-fold increase over the control at the respective molar ratios of Au-apoferritin and Ag-apoferritin nanoparticles (NPs) of 500:1 and 1000:1. Typical color change, from pale yellow to brown, occurred when apoferritin was mixed with AgNO(3) or AuCl(3) followed by sodium borohydride to afford respective metal-apoferritin NP complexes in a ratio of between 250:1 and 4000:1. These complexes were characterized by ultraviolet-visible inductively coupled plasma-optical emission spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and energy-dispersive x-ray spectroscopy. Transmission electron microscopy revealed that the size of NPs increased as the molar ratio of metal to apoferritin increased, with an average size of 3-6 nm generated with Au-to-apoferritin and/or Ag-to-apoferritin molar ratios of 250:1 to 4000:1. Fourier transform infrared spectrometry showed no structural changes of apoferritin when the NPs were attached to the protein.
In this paper the utility of gold and silver nanoparticles in augmenting the activity of the ferroxidase-apoferritin complex is described. Both NPs dramatically increased the ferroxidase activity.
银（Ag）和金（Au）纳米粒子对脱铁蛋白的亚铁氧化酶活性的影响表明，在金-脱铁蛋白和银-脱铁蛋白纳米粒子（NPs）的摩尔比分别为 500:1 和 1000:1 时，比活度分别提高了 110 倍和 9 倍。当脱铁蛋白与 AgNO(3)或 AuCl(3)混合后，再加入硼氢化钠，发生典型的颜色变化，从浅黄色变为棕色，从而在 250:1 至 4000:1 的比例下获得相应的金属-脱铁蛋白 NP 复合物。这些复合物通过紫外可见电感耦合等离子体发射光谱、傅里叶变换红外光谱、透射电子显微镜和能量色散 X 射线光谱进行了表征。透射电子显微镜显示，随着金属与脱铁蛋白摩尔比的增加，纳米粒子的尺寸增大，当 Au 与脱铁蛋白和/或 Ag 与脱铁蛋白的摩尔比为 250:1 至 4000:1 时，平均粒径为 3-6nm。傅里叶变换红外光谱显示，当 NPs 附着在蛋白质上时，脱铁蛋白的结构没有发生变化。
本文描述了金和银纳米粒子在增强亚铁氧化酶-脱铁蛋白复合物活性方面的应用。两种纳米粒子都显著提高了亚铁氧化酶的活性。
